[evince] Add .png extension when saving images using DnD

[Wouter Bolsterlee <wbolster src gnome org>]

commit 7069b43e9a64be2d4e4509dffd0384dfcce59de4
Author: Wouter Bolsterlee <wbolster gnome org>
Date:   Thu Mar 3 19:28:23 2011 +0100

    Add .png extension when saving images using DnD
    
    Bug #643709 â?? No file name extension when dragging images to Nautilus.
    https://bugzilla.gnome.org/show_bug.cgi?id=643709

 libdocument/ev-image.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/libdocument/ev-image.c b/libdocument/ev-image.c
index e02831e..fcbbd7d 100644
--- a/libdocument/ev-image.c
+++ b/libdocument/ev-image.c
@@ -144,8 +144,8 @@ ev_image_save_tmp (EvImage   *image,
 	if (image->priv->tmp_uri)
 		return image->priv->tmp_uri;
 
-        if ((fd = ev_mkstemp ("image.XXXXXX", &filename, &error)) == -1)
-                goto had_error;
+	if ((fd = ev_mkstemp ("image.XXXXXX.png", &filename, &error)) == -1)
+		goto had_error;
 
 	gdk_pixbuf_save (pixbuf, filename,
 			 "png", &error,